Triceps, Posterior View

Description

Posterior anatomy of the male upper limb centers on the triceps brachii draped over the posterior humerus, with the long head forming a medial column from the infraglenoid tubercle of the scapula and the lateral head bulking the posterolateral arm. Distally, the three heads converge into a broad triceps tendon inserting on the olecranon of the ulna, lying superficial to the posterior elbow capsule and olecranon bursa. The posterior deltoid caps the proximal arm superiorly, while the scapular spine and acromion frame the shoulder girdle; more inferiorly, latissimus dorsi and the thoracolumbar erector spinae define the posterior trunk around the arm. Depth matters here because the triceps is more than a surface contour: deep to the lateral head, the radial nerve and profunda brachii artery course in the spiral (radial) groove of the humerus, a relationship that explains wrist drop after midshaft humeral fractures and guides safe dissection in posterior approaches. The long head also forms the medial border of the quadrangular space and a boundary of the triangular interval, where the radial nerve exits to the posterior compartment. Elbow extension strength is judged clinically at this tendon. Simple, but unforgiving. Use this posterior view to teach compartment anatomy in gross anatomy, kinesiology, and sports medicine modules, or to illustrate operative planning for triceps-splitting versus triceps-reflecting exposure in distal humerus fixation and elbow arthroplasty, where protecting the ulnar nerve medially and the radial nerve proximally is procedural reality. It also suits patient-facing diagrams for triceps tendon rupture, olecranon bursitis, and posterior shoulder injections that require clear surface landmarks around the deltoid and scapular spine. Anatomical accuracy verified by SciePro's Medical Advisory Board.